CVE-2019-5544
Confirmed PUBLISHEDOpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the...
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the Critical severity range with a maximum CVSSv3 base score of 9.8.
- CVE Published
- Dec 06, 2019
- Exploitation Reported
- Nov 03, 2021
- CVSS
- 9.8 Critical
- EPSS
- —
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| n/a |
ESXi and Horizon DaaS
|
ESXi 6.7 prior to patch release ESXi670-201912001, ESXi 6.5 prior to patch release ESXi650-201912001, ESXi 6.0 prior to patch release ESXi600-201912001 and Horizon DaaS 8.x prior to BZ-2467224-Disable_SLPD_service_permanently_801_Hotfix. |
Affected |
CVE References
- RHSA-2019:4240 access.redhat.com · Vendor Advisory https://access.redhat.com/errata/RHSA-2019:4240
- FEDORA-2019-1e5ae33e87 lists.fedoraproject.org · Vendor Advisory https://lists.fedoraproject.org/archives/list/package-announce%40list...
- FEDORA-2019-86bceb61b3 lists.fedoraproject.org · Vendor Advisory https://lists.fedoraproject.org/archives/list/package-announce%40list...
- RHSA-2020:0199 access.redhat.com · Vendor Advisory https://access.redhat.com/errata/RHSA-2020:0199
- GLSA-202005-12 security.gentoo.org · Vendor Advisory https://security.gentoo.org/glsa/202005-12
Show 3 more references
- [oss-security] 20191210 Re: CVE-2019-5544 openslp 1.2.1, 2.0.0 heap overflow vulnerability openwall.com · Mailing List http://www.openwall.com/lists/oss-security/2019/12/10/2
- [oss-security] 20191211 Re: CVE-2019-5544 openslp 1.2.1, 2.0.0 heap overflow vulnerability openwall.com · Mailing List http://www.openwall.com/lists/oss-security/2019/12/11/2
- vmware.com/security/advisories/VMSA-2019-0022.html vmware.com · CVE Record http://www.vmware.com/security/advisories/VMSA-2019-0022.html
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CISA First | 2021-11-03 00:00 UTC |
Scanner Artifacts
Nuclei and Metasploit references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/network/cves/2019/CVE-2019-5544.yaml | Jun 01, 2026 |
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:L/Au:N/C:P/I:P/A:P
Exploitation Status
Exploited in the wild
Recorded 2021-11-03 00:00:00 UTC · CISA
Used in malware
Recorded 2021-11-03 00:00:00 UTC · CISA
Proof of concept available
Recorded 2020-12-01 13:49:26 UTC · GitHub
Weaknesses (CWE)
-
Out-of-bounds Write
Scanner Integrations
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/network/cves/2019/CVE-2019-5544.yaml | Jun 01, 2026 |
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
github · Created 2020-12-01 13:49:26 UTC · 48 stars
Python / scapy module implementing SRVLOC/SLP protocol and scans for enabled OpenSLP services.
nuclei · Created Unknown
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
15:34 UTC about 2 months ago15:34 UTC · about 2 months ago
Nuclei template available
Scanner coverage available
-
00:00 UTC over 4 years ago00:00 UTC · over 4 years ago
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
00:00 UTC over 4 years ago00:00 UTC · over 4 years ago
First public exploitation report
Exploit observed in malware
-
13:49 UTC over 5 years ago13:49 UTC · over 5 years ago
Public PoC available
Public proof-of-concept code published
-
15:54 UTC over 6 years ago15:54 UTC · over 6 years ago
CVE published
Vulnerability disclosed publicly
-
00:00 UTC over 7 years ago00:00 UTC · over 7 years ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2019-5544
{
"cve_id": "CVE-2019-5544",
"title": "OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite ...",
"affected_vendor": "VMware",
"affected_product": "ESXi and Horizon DaaS",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 9.8,
"epss_score": null,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}